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I'm use Live CD.....................
ubuntu@ubuntu:~$ sudo df
Filesystem 1K-blocks Used Available Use% Mounted on
tmpfs 1553380 16512 1536868 2% /lib/modules/2.6.24-19-generic/volatile
tmpfs 1553380 16512 1536868 2% /lib/modules/2.6.24-19-generic/volatile
varrun 1553380 104 1553276 1% /var/run
varlock 1553380 0 1553380 0% /var/lock
udev 1553380 52 1553328 1% /dev
devshm 1553380 148 1553232 1% /dev/shm
tmpfs 1553380 16 1553364 1% /tmp
/dev/sdb1 74328480 16051608 54530920 23% /media/disk
/dev/sda2 156191960 102650552 53541408 66% /media/disk-1
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ubuntu@ubuntu:~$ sudo fdisk -l

Disk /dev/sda: 160.0 GB, 160000000000 bytes
255 heads, 63 sectors/track, 19452 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xd0f4738c

Device Boot Start End Blocks Id System
/dev/sda1 1 6 48163+ de Dell Utility
/dev/sda2 * 7 19451 156191962+ 7 HPFS/NTFS

Disk /dev/sdb: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x0002de00

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 9327 74919096 6 FAT16
/dev/sdb2 9328 9729 3229065 5 Extended
/dev/sdb5 9328 9729 3229033+ 82 Linux s
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grub> root (hd0,
Possible partitions are:
Partition num: 0, Filesystem type unknown, partition type 0xde
Partition num: 1, Filesystem type unknown, partition type 0x7

grub> root (hd1,
Possible partitions are:
Partition num: 0, Filesystem type unknown, partition type 0x6
Partition num: 4, Filesystem type unknown, partition type 0x82
为什么我的grub＞root hd0和１都没有显示任何系统？
之前我的dev/sdb1是显示Linux,现在是FAT16!!!
要如何改呢？？很烦。。。